Hard to tell. Maybe a multinucleate cell? Could be caused by the treatment.

https://en.wikipedia.org/wiki/Multinucleate

Other option could be some insect eggs. I don't think these are vacuoles, as they seem to have DNA in them.

The structures are chlamydospores of a mycorrhizal fungus. They look quite similiar to Pirirsporoformis indica which produces these in chains. This maybe a cultivatable fungus of basidiomycete alignment. You might want to test for cultivating it. In the case of P. indica it does have great beneficial potential and people are excited about the ability to increase it in laboratory culture. P. indica is know to take to wheat and have positive effects. If you can cultire it the best indication of positive would be PCR analysis of the genetic material.

i think it is the answer of your question..

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